Fair value of the forward option net asset (liability).

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

+ Details

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Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Investment in NEC TOKIN - Stock Purchase Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017	Jun. 30, 2016	Jun. 30, 2015	Mar. 12, 2012	May 05, 2010
Schedule of Equity Method Investments [Line Items]
Change in value of NEC TOKIN option	$ 0	$ 1,600	$ 0	$ (10,400)
Derivative Assets (Liabilities), at Fair Value, Net	$ 0		0		$ (9,900)
Recurring
Schedule of Equity Method Investments [Line Items]
Change in value of NEC TOKIN option			$ 9,900
Senior Notes [Member]
Schedule of Equity Method Investments [Line Items]
Rate									10.50%
NEC TOKIN Corporation [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	34.00%		34.00%				34.00%
NEC TOKIN Corporation [Member] \| Put Option [Member]
Schedule of Equity Method Investments [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ (9,900)		$ (9,900)
NEC TOKIN Corporation [Member] \| KEMET Electronics Corporation [Member] \| Stock Purchase Agreement [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						34.00%		34.00%